# FAQ ## Frequently asked questions ### What is the fastest way to try Rierino?
Show answer The fastest path is the free Community Edition on AWS Marketplace. It gives you a ready-to-use environment for exploring the platform and validating the architecture quickly. See [Installation](https://docs.rierino.com/quick-start/installation).
### Do I need to install everything myself first?
Show answer No. You can start with the hosted marketplace option first. Use custom installation when you need a licensed, self-managed setup for your own environment. Common self-managed options are a single VM with Docker Compose or Kubernetes with Helm. See [Installation](https://docs.rierino.com/quick-start/installation).
### Which data store should I expect by default?
Show answer Most standard setups use MongoDB as the main data store. That is a good default for training, initial development, and many early projects.
### Where do I define secrets and connection settings?
Show answer Keep secrets and connection values outside the UI when possible. On a single VM, they usually live in `globalconfig.properties` and `globalsecrets.properties`. On Kubernetes, they are commonly stored in ConfigMaps and Secrets. See [Installation](https://docs.rierino.com/quick-start/installation).
### What is the main entry point in the Admin UI?
Show answer The global home page is the main landing page. It shows accessible screens, AI agents, quick links, favorites, and recent pages. See [Layout & Navigation](https://docs.rierino.com/quick-start/layout-and-navigation).
### What is an app home page?
Show answer Each app has its own landing page. It usually includes modules, profile details, and app-specific FAQs. It acts as the local starting point once you enter an app. See [Layout & Navigation](https://docs.rierino.com/quick-start/layout-and-navigation).
### How do users usually navigate in Rierino?
Show answer Most users follow a simple flow: 1. Open the global home page. 2. Switch to the right app. 3. Open a screen. 4. Find a record in the lister. 5. Open or edit it in the editor. See [Layout & Navigation](https://docs.rierino.com/quick-start/layout-and-navigation).
### What is the difference between a lister and an editor?
Show answer The lister is for finding, filtering, sorting, and selecting records. The editor is for viewing, creating, and updating a selected record. Most screens use both together. See [Layout & Navigation](https://docs.rierino.com/quick-start/layout-and-navigation).
### Which app should I use to build backend services?
Show answer Use **Devops**. That is where you define runners, sagas, gateway routing, security, and deployments. See [Development](https://docs.rierino.com/quick-start/development).
### Which app should I use for reusable logic like queries and rules?
Show answer Use **Configuration**. That is where you define reusable queries, business rules, and dynamic handlers that can run at runtime without redeploying services. See [Development](https://docs.rierino.com/quick-start/development).
### Which app should I use to build the admin UI?
Show answer Use **Design**. That is where you define apps, UIs, widgets, listers, and source mappings that connect the UI to backend APIs. See [Development](https://docs.rierino.com/quick-start/development).
### Which app should I use for AI and ML features?
Show answer Use **Data Science**. That is where you manage ML models, GenAI models, MCP servers, visualizations, and related assets. See [Development](https://docs.rierino.com/quick-start/development).
### What should I read first if I am brand new?
Show answer Start with [Development](https://docs.rierino.com/quick-start/development). Then review the training examples and the guided starting paths. That gives you the quickest mental model of how the platform fits together. See [I would like to start with...](https://docs.rierino.com/quick-start/i-would-like-to-start-with...).
### I want a standard CRUD API. Where should I start?
Show answer Start with the CRUD service path. That is the fastest route when you need standard create, read, update, and delete behavior on a collection or table. See [I would like to start with...](https://docs.rierino.com/quick-start/i-would-like-to-start-with...).
### I want a custom API endpoint. Where should I start?
Show answer Start with an API endpoint built as a saga. This is the right path when you need custom validation, transformation, branching, or aggregation logic. See [I would like to start with...](https://docs.rierino.com/quick-start/i-would-like-to-start-with...).
### I want to integrate multiple systems. Where should I start?
Show answer Start with the integration or orchestration path. Use this when you need to call third-party APIs, combine internal services, or coordinate retries, batching, and transformations. See [I would like to start with...](https://docs.rierino.com/quick-start/i-would-like-to-start-with...).
### I want to build an internal app. Where should I start?
Show answer Start with the internal application path. Use this when you need forms, lists, editors, and back-office workflows without building a custom front-end first. See [I would like to start with...](https://docs.rierino.com/quick-start/i-would-like-to-start-with...).
### I want to build an AI agent. Where should I start?
Show answer Start with the AI agent path. Rierino agents usually combine a governed GenAI model with tool sagas or tool states, plus optional interfaces. See [I would like to start with...](https://docs.rierino.com/quick-start/i-would-like-to-start-with...).
### What if I am not sure which path fits?
Show answer Use this quick rule: * Need standard data APIs fast → start with CRUD service * Need custom business endpoints → start with API endpoint * Need multi-system coordination → start with integration or orchestration * Need an internal screen → start with internal application * Need conversational automation → start with AI agent If you want one guided path that touches most core concepts, start with the [In-depth Exercise](https://docs.rierino.com/examples/in-depth-exercise).
### What should I check first if something does not work?
Show answer Start with the basics: * Confirm the gateway is reachable * Confirm the training microservices are deployed * Confirm the main data store is accessible Then review error codes, common checks, and release notes if needed. See [Development](https://docs.rierino.com/quick-start/development).